SummaryDoyenné du Comice pear was grown for 11 years on four dwarfing quince rootstocks of Caucasian origin in comparison with trees on Quince A and Quince C. The trees on Quince C were about 23% less vigorous than those on Quince A but gave the heaviest yield, particularly in the early years though with some reduction in fruit size. A Caucasian clone, C132, was less precocious than Quince C but gave trees of similar vigour which cropped as well as those on Quince C in the later years and produced larger fruits. These results were largely confirmed by trials on a range of sites, though on good soil Quince C showed less tendency to bear small fruit. Conference pear on Quince C was 27% less vigorous than on Quince A but produced a slightly higher yield per tree.